wiring diagram ISUZU TF SERIES 2004 Workshop Manual

9A1-4 RESTRAINT CONTROL SYSTEM

cautions in the service manual and on warning labels
attached to SRS components.

Basic Electrical Circuits
You should understand the basic theory of electricity
including series and parallel circuits, and understand
the voltage drops across series resistors. You should
know the meaning of voltage (volts), current (amps),
and resistance (ohms). You should understand what
happens in a circuit with an open or a shorted wire. You
should be able to read and understand a wiring
diagram.

“Flash Code” Diagnostics
Flash code diagnostics can be used to read active
codes and to determine if history codes are present but
cannot be used to clear codes or read history codes.
Flash code diagnostics is enabled by grounding by
terminal 4 shorting to terminal 13 of the DLC connector
with the ignition switch “ON”. Grounding terminal 4 of
the DLC connector pulls the “Diagnostics Request”
input (Terminal 1) of the SRS control unit low and
signals the SRS control unit to enter the flash code
diagnostic display mode.


060R300052

ELECTRICAL-BODY AND CHASSIS 8A-1
SECTION 8A
ELECTRICAL-BODY AND CHASSIS
TABLE OF CONTENTS
PAGE
General Information ........................................................................................................ 8A- 4
Notes for Working on Electrical Items .......................................................................... 8A- 5
Symbols and Abbreviations ........................................................................................... 8A- 11
Symbols ...................................................................................................................... 8A- 11
Abbreviations ............................................................................................................. 8A- 12
Parts for Electrical Circuit .............................................................................................. 8A- 13
Wiring .......................................................................................................................... 8A- 13
Fuse ............................................................................................................................. 8A- 15
Fusible Link ................................................................................................................ 8A- 15
Relay ............................................................................................................................ 8A- 16
Diode ........................................................................................................................... 8A- 17
Connector ................................................................................................................... 8A- 18
Battery ......................................................................................................................... 8A- 19
Reading the Circuit Diagram .......................................................................................... 8A- 22
Parts Location ............................................................................................................ 8A- 22
Circuit Diagram ........................................................................................................... 8A- 23
Connector List ............................................................................................................. 8A- 23
Main Data and Specifications ........................................................................................ 8A- 24
Bulb Specifications .................................................................................................... 8A- 24
Relay and Fuse ................................................................................................................ 8A- 26
Relay and Fuse Box Location ................................................................................... 8A- 26
Relay Location ............................................................................................................ 8A- 28

ELECTRICAL-BODY AND CHASSIS 8A-13
PARTS FOR ELECTRICAL CIRCUIT


WIRING
Wire Color
All wires have color-coded insulation.
Wires belonging to system's main harness will have a single
color.
Wires belonging to a system's sub-circuits will have a colored
stripe.
Striped wires use the following code to show wire size and
colors.
Example: 0.5 G
/ R
Red (Stripe color)
Green (Base color)
Wire size (0.5mm
2)
Abbreviations are used to indicate wire color within a circuit
diagram.
Refer to the following table.


Wire Color-Coding
Color-Coding Meaning Color-Coding Meaning
B Black BR Brown
W White LG Light green
R Red GR Grey
G Green P Pink
Y Yellow LB Light blue
L Blue V Violet
O Orange

8A-16 ELECTRICAL-BODY AND CHASSIS


RELAY
Battery and load location may require that a switch be placed
some distance from either component.
This means a longer wire and a higher voltage drop
1. The
installation of a relay between the battery and the load reduces
the voltage drop
2.
Because the switch controls the relay, amperage through the
switch can be reduced.


Relay Specifications and Configurations
Name/
Color Rated
voltage/ Coil
resistance Internal circuit Name/
color Rated
Voltage/Coil
resistance Internal circuit
1T
(MICRO
ISO)
/Black 12V
Approx. 92
Minimum
operating
voltage: 7V at
20C (77F)

1M (MINI
ISO)
/Black 12V Approx.
94 Minimum
operating
voltage: 7V at
20C (77F)

1M
(MICRO
ISO)
/Black 12V
Approx. 132-3
 Minimum
operating
voltage: 7V at
20C (77F)

1M
(power)/
Black 12V Approx.
94 Minimum
operating
voltage: 7V at
20C (77F)

* Relay contact shown in the wiring diagram indicates condition before actuation.

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–1
ENGINE
CONTENTS
4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
ABBREVIATION CHARTS ........................ 6E-9
4JA1-TC .................................................... 6E-10
4JH1-TC .................................................... 6E-11
ECM CIRCUIT DIAGRAM (4JA1-TC) ........ 6E-14
ECM CIRCUIT DIAGRAM (4JA1-TC) ........ 6E-15
ECM CIRCUIT DIAGRAM (4JH1-TC) ........ 6E-16
ECM CIRCUIT DIAGRAM (4JH1-TC) ........ 6E-17
GROUND POINT CHART GENERAL EXPORT
(LHD) (1/4) ............................................... 6E-18
LOCATION ................................................ 6E-34
PARTS LOCATION ................................... 6E-39
CONNECTOR LIST ................................... 6E-40
RELAY AND FUSE .................................... 6E-43
RELAY AND FUSE BOX LOCATION
(LHD & RHD) ........................................... 6E-43
RELAY AND FUSE BOX LOCATION
(LHD & RHD) ........................................... 6E-44
FUSE AND RELAY LOCATION (LHD & RHD) 6E-45
ECM WIRING DIAGRAM (1/7) .................. 6E-46
ECM WIRING DIAGRAM (2/7) .................. 6E-47
ECM WIRING DIAGRAM (3/7) .................. 6E-48
ECM WIRING DIAGRAM (4/7) .................. 6E-49
ECM WIRING DIAGRAM (5/7) .................. 6E-50
ECM WIRING DIAGRAM (6/7) .................. 6E-51
ECM WIRING DIAGRAM (7/7) .................. 6E-52
ECM CONNECTOR PIN ASSIGNMENT &
OUTPUT SIGNAL .................................... 6E-53
GENERAL DESCRIPTION FOR ECM AND
SENSORS ............................................... 6E-64
Engine Control Module (ECM) ................... 6E-64
Pump Control Unit (PSG) & Data Ex change
Between Control Module ......................... 6E-64
Mass Air Flow (MAF) Sensor & Intake Air
Temperature (IAT) Sensor ....................... 6E-65
Throttle Position Sensor (TPS) .................. 6E-66
Crankshaft Position (CKP) Sensor ............ 6E-66
Engine Coolant Temperature (ECT) Sensor 6E-67
Vehicle Speed Sensor (VSS) .................... 6E-67
GENERAL DESCRIPTION FOR EGR
(EXHAUST GAS RE-CIRCULATION) ..... 6E-68
GENERAL DESCRIPTION FOR
INJECTION PUMP .................................. 6E-70Outline ....................................................... 6E-70
Cross-section View .................................... 6E-70
Low Pressure Fuel Circuit .......................... 6E-71
High Pressure Fuel Circuit ......................... 6E-72
Pump Camshaft Speed Sensor ................. 6E-72
High Pressure Solenoid Valve ................... 6E-73
Timing Control Valve (TCV) ....................... 6E-74
ISUZU Strategy Based Diagnostics .............. 6E-76
Overview .................................................... 6E-76
STRATEGY BASED DIAGNOSTICS CHART 6E-76
Diagnostic Thought Process ...................... 6E-77
1. Verify the Complaint .............................. 6E-77
2. Perform Preliminary Checks .................. 6E-77
3. Check Bulletins and Troubleshooting Hints 6E-78
4. Perform Service Manual Diagnostic Checks 6E-78
5a and 5b. Perform Service Manual Diagnostic
Procedures .............................................. 6E-78
5c. Technician Self Diagnoses .................. 6E-78
5d. Intermittent Diagnosis .......................... 6E-79
5e. Vehicle Operates as Designed ............ 6E-80
6. Re-examine the complaint ..................... 6E-81
7. Repair and Verify Fix ............................. 6E-81
GENERAL SERVICE INFORMATION ....... 6E-82
ON-BOARD DIAGNOSTIC (OBD) ............. 6E-82
TECH 2 OPERATING FLOW CART
(START UP) ............................................. 6E-86
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ................................... 6E-88
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ................................... 6E-90
MISCELLANEOUS TEST .......................... 6E-92
Plotting Snapshot Graph ............................ 6E-93
Plotting Graph Flow Chart (Plotting graph
after obtaining vehicle information) .......... 6E-94
Flow Chart for Snapshot Replay
(Plotting Graph) ....................................... 6E-95
SNAPSHOT DISPLAY WITH TIS2000 ...... 6E-96
ON-BOARD DIAGNOSTIC (OBD) SYSTEM
CHECK .................................................... 6E-105
Circuit Description ...................................... 6E-105
Diagnostic Aids .......................................... 6E-105
Test Description ......................................... 6E-105

6E–46 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
ECM WIRING DIAGRAM (1/7)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–47
ECM WIRING DIAGRAM (2/7)

6E–48 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
ECM WIRING DIAGRAM (3/7)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–49
ECM WIRING DIAGRAM (4/7)

6E–50 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
ECM WIRING DIAGRAM (5/7)